Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2019

Financial Instruments, Owned, at Fair Value [Abstract]

Estimated Fair Values of Financial Instruments

The following table presents the fair values of financial instruments:

	December 31,
	2019		2018
	(Amounts in thousands)
Assets
Investments	$	4,312,161	$	3,768,091
Note receivable	5,665		5,557
Liabilities
Total return swaps	—		4,851
Options sold	77		3
Unsecured notes	394,279		362,674